The present invention is generally related to retroreflective garments and, more particularly, is related to garments that are constructed of retroreflective fabrics.
Retroreflectivity is a characteristic in which obliquely incident light is reflected in the same direction to the incident direction such that an observer at or near the light source receives the reflected light. This unique characteristic has led to the wide-spread use of retroreflective materials on various substrates because substrates coated with retroreflective materials are more easily identified during nighttime conditions. For example, retroreflective articles can be used on flat inflexible substrates, such as road signs and barricades; on irregular surfaces, such as corrugated metal truck trailers, license plates, and traffic barriers; and on flexible substrates, such as road construction personnel safety vests, running shoes, roll-up signs, and canvas-sided trucks.
There are two major types of retroreflective materials: beaded materials and cube-corner materials. Beaded materials commonly use a multitude of glass or ceramic microspheres partially coated with a specular reflective coating to retroreflect incident light. Typically, the microspheres are partially embedded in a support film, where the specular reflective coating is adjacent the support film. The reflective coating can be a metal coating such as, for example, an aluminum coating, or an inorganic dielectric mirror made up of multiple layers of inorganic materials that have different refractive indices.
In lieu of microspheres, cube-corner articles typically employ a multitude of cube-corner elements to retroreflect incident light. The cube-corner elements project from the back surface of a body layer. In this configuration, incident light enters the sheet at a front surface, passes through the body layer to be internally reflected by the faces of the cube-corner elements, and subsequently exits the front surface to be returned towards the light source. Reflection at the cube-corner faces can occur by total internal reflection when the cube-corner elements are encased in a lower refractive index media (e.g. air) or by reflection off a specular reflective coating such as a vapor deposited aluminum film.
Retroreflective articles typically include a layer of retroreflective optical elements, microspheres, and/or cube-cornered elements, coated with a specular reflective coating. Generally, the retroreflective elements are embedded in a binder layer attached to the article. Typically, the optical elements are transparent microspheres that are partially embedded in the binder layer such that a substantial portion of each microsphere protrudes from the binder layer. The specular reflective coating is disposed on the portion of the transparent microsphere, which is embedded in the binder layer. Light striking the front surface of the retroreflective articles passes through the transparent microspheres, is reflected by the specular reflective coating, and is collimated by the transparent microspheres to travel back in a direction parallel to the incident light.
As discussed above, the use of retroreflective articles is widespread. For example, road construction personnel, utility personnel, and firefighter personnel often wear retroreflective clothing to make the wearer conspicuously visible at nighttime. The retroreflective articles displayed on this clothing typically comprises retroreflective stripes. Unfortunately, retroreflective stripes can have several significant drawbacks. For example, clothing provided with retroreflective stripes only reflects light from the stripe. Consequently, the person observing the reflected light may not be able to differentiate the reflecting stripes as representing a person, sign, or other obstacle. Further, if the person wearing the reflective stripe is positioned such that the stripe is blocked from the light, then the reflective stripe is ineffective. An additional disadvantage is that excessive layers of retroreflective material can make the garments heavier, less flexible, and can increase product cost.
Thus, a heretofore unaddressed need exists in the industry to provide garments that address the aforementioned deficiencies and inadequacies.
Embodiments of the present invention provide for a retroreflective garment constructed of flame resistant fabric. The garment is light-weight and single or double layered. Garments that can be constructed of flame resistant fabric with a plurality of retroreflective elements directly applied thereon include garments such as, for example, shirts, pants, coveralls, jumpsuits, jackets, gloves, hats, etc. The flame resistant fabric has a coefficient of retroreflection of about 10 to about 500 candelas per lux per square meter. In addition, the plurality of retroreflective elements covers at least about 5 percent of the outer surface of the flame resistant fabric. The flame resistant fabric is composed of flame resistant fibers such as, for example, aramid fibers, polybenzimidazole fibers, polybenzoxazole fibers, melamine fibers, flame resistant rayon, flame resistant cotton, or blends thereof.
Another embodiment provides for a method of constructing a retroreflective garment that is light-weight and is either single or double layered. The method includes applying the outer surface of the flame resistant fabric with a plurality of retroreflective elements and constructing a light-weight, retroreflective garment from the flame resistant fabric so that the outer surface that has the plurality of retroreflective elements applied thereon faces away from the body of the wearer. The plurality of retroreflective elements can be applied to the flame resistant fabric by process techniques such as, for example, flat screen printing techniques, rotary screen printing techniques, and retroreflective transfer film techniques.
Other systems, methods, features, and advantages of the present invention will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.